Rock drill



Nov. 13, 1928.

C. F. OSGOOD ROCK DRILL Filed June 2, 1927 172706771507: iz/arlesl." Osgood;

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Atty.

Patented Nov. 13, 1928. I i y UNITED STATES PATENT OFF-ICE.

CHARLES E. oseoon, or oLARnMoiv'r, N'EW HAnPSH'InE, ASSIGNOB, r SULLIVAN MACHINERY COMPANY, A CORPORATION or MASSACHUSETTS.

' I 7 ROCK DRILL.

Application filed June 2, 1927. SerialNo. 196,109

This invention relates to. rock drills and trat-ed, the rear end ofthe cylinder bore 2 is more particularly to a hole blowing device closed by a washer 11 while interposed befor fluid actuated rock drills of the hammer tween this washer and a rear head member 12 type. r is a usual ratchet ring 13 to be later referred An object of this invention is to provide to. The chuck housing 10, the front cylinder an improved hole'blowing device for a fluid head 6, the cylinder 1,rear washer 11, rear- 60 actuated rock drill. Another object is to head 12, and the ratchet ring 13 are held in provide an improved hole blowing device assembled relation in any suitable and con-v whereby the opposing pressures acting on the venient manner, for instance by usual side opposite ends of the fluid distribution valve rods or bolts (not shown). I

may be equalized prior to the manual shift- Thec linder 1 has preferably formed in- 65 ing of the valve, thereby greatly reducing tegral t erewith a valve chest 14 having a the exertion required on the part of the opbore 15, herein arranged parallel with the erator. Another object is to provide an imcylinder bore 2. Disposed within the bore 15 proved hole blowing device for holding the 15 are oppositely positioned valve sleeves 16 fluid distribution valve immovable to effect and 17 each having an enlarged" central bore 70 a hole blowing operation and including a 18, and a reduced outer bore 19. As shown manually operable plunge-r valve extending in Fig. 1, the valve sleeve 16 has suitably coaxially through the distribution valve and fixed thereto a valve buffer plug-'20 while se- 20 having a by-pass therein whereby communicured to the sleeve 17'is a buffer plug 21 held cation between the spaces at the ends of the in position by a suitable nut member 22. Res 70 distribution valve may beestablished, and ciprocably mounted within the bores 18 and as a result the opposing pressures at the ends 19 formed in the sleeves 16 and 17 is an auto-' of the distribution valve may be equalized matic fluid distribution valve 23 herein of prior to the manual shifting thereof. These the well known three-spool, differential type and other objects and advantages will, howhaving reduced end spools 24 and an enlarged 80 ever, subsequently more fully appear. central spool 25. Reciprocating movement In the accompanying drawing there is of the valve 23 inopposite directions is li1n-' I shown for purposes of illustration one form lted by the buffer plugs 20 and 21 in a well which the invention may assume in practice. known manner. The central spool 25 of the In this drawing,1 1 Valve shown controls a central inlet port 26, Fig. 1 is a central, longitudinally extends while the end spools 24 respectively control ing, vertical sectional view taken through a usual exhaust ports 27 and 28 formed at the rock drill with which the improved hole opposite sides of the inlet port 26 and leadblowing device is incorporated. ing directly to atmosphere; Motive fluid for Figs. 2 andB are detail sectional views actuating the piston 3 is supplied and-exillustrating the automatic fluid distribution haus'te d from the rear and front ends of the valve and the hole blowing device associated cylinder bore 2 through contibined supply and therewith, parts being shown in different opexhaust passages 29 and 30 respectively com- 40 erative positions. municating with the valve chamber on oppo- In this illustrative construction there is site sides of the central inlet-'26. The action 5 shown a rock drill of the fluid actuated haniof thevalve 23 is controlled byusual crossed iner type comprising a cylinder 1 having a throwing passages 31 and 32, the former conbore 2 in which is reciprocablymounted a necting the front endt'of the cylinder bore hammer piston 3. The hammer piston 3 is with the bore 19 at the rear end of the valve,

provided with a forwardly projecting strike while the throwing passage '32 connects the ing bar it extending through a bore 5 formed rear end of the cylinder bore with the bore within a usual front cylinder-head 6. The 19 at the front end of the valve. These.

striking bar 4; is adapted to'irnparta series throwing passages are controlled by the ham- 50 of blows to the shank of a. hollow drill steel mer piston 3 and are employed for alterna- 7. -The drill steel 7 isloosely mounted in a tively admitting pressure fluid from the cylusual manner within a. chuck bushing 8 seinder bore to the opposite. ends of'the discured to a chuck sleeve 9 rotatably mounted tributionvalve to eflec t reciprocation therewithin a usual chuck housing 10. As illusof, the pressure fluid admitted to the pa sage 31 throwing the distribution valve forwardly while the pressure fluid admitted to the passage 32 throws the valverearwardly, all in a well known manner. v

The drill steel 7 is adapted to be intermittently rotated during reciprocation of the iammer piston and this is accomplished a usual ratchet and pawl mechanism including a rotatable pawl carrier 33 carrying usual spring pressed-pawls which cooperate with internal ratchet teeth 34 formed within the ratchet ring 13; .Herein preferably formed integral with thispawl carrier and projecting forwardly through the washer 11 and within the rear end of the cylinder bore is arifle bar 35 having spiral grooves 36 on its'periphery. The spiral grooves 36 cooperate with Spiralkeys 37 carried by a rifle nut 38 threadedly connected Within the rear end of the hammer piston 3. As shown, the striking bar 4 of the hammer piston-has formed on its periphery throughout a portion of its length straight longitudinally extending grooves 39 which cooperate with straight keys 40 carried by achuck-nut 41 threadedly connected to the chuck sleeve 9. During forward movement of the hammer piston 3 the pawls of the pawl carrier slip over the teeth on the ratchet ring 13 and consequently the hammer piston delivers anunimpeded blow to the shank of the drillsteel 7. Upon'the return stroke of the iammer piston the pawls engage the ratchet teeth 34, thereby preventing rotation of the rifle bar and consequently during this return stroke of the hammer piston the latter is slightly rotated. Rotation of the piston is transmitted through the straight grooves 39 011 the striking bar, straight keys 40 on the chuck nut, the sleeve 9 and the chuckbushing 81 and consequently the drill steel is rotated. The construction described above is usual in rock drills of-the type disclosed andfurther description of the same is herein considered 20 is reduced, thereby forming ashoulder or abutment 46 adapted to engage the distribution valve as will hereinafter be described. The valve 42 is externally grooved at longitudinally spaced points as indicated at 47 and 48, and these grooves are connected by transverse passages 49 and a central longitudinally extending passage 50, the passages 49 and 50 forming a by-pass. As shown, radial ports 4 51 and 52 connect thebores 44 and 45 respectively in the buffer plugs with the bores 19 atthe endsof the distribution valve 23. Suitably secured to the forward end of the valve from the position shown in Fig. to the nosi 42 is a conveniently located push button53. 1 A coiled spring 54 seated within a bore 55 formed in the buffer plug 21 and acting against a transverse pin 56 carried by the plunger valve 42 normally tends to hold the valve 42 in its released 'or inoperative posi tion, as shown'in Fig. 3.

y In the normal operation of the rock drill, pressure fluid flows through inlet passage 26 and when the distribution valve 23 is in the position shown in Fig. 2, fluid flows past'the rear surface of the central spool25of the distributioi'rvalve and through'the passage 29 fto, the rear end of the cylinder bore 2 where it acts on the rear surface of the hammer piston 3 and moves the latter forwardly to strike a.

blow on the drill steel 7. The exhaust from the front end of the cylinderbore '2 flows out through the passage 30 past the rear surface of the forward spool 24 and through the exhaust passage 28 to atmosphere. The distribution valve is held in its forward position against the front buffer plug21 by reason of the larger eifectivearea of the central spool 25. Nhen'the hammer piston 3 uncovers the throwing passage 32, pressure fluid is ad mitted from the cylinder bore to theforward, end ofthe distribution valve and consequently the latter is thrown rearwardly against the rear buffer plug 20 as shown in Fig. 1. Pressure fluid now enters the forward end of the cylinder; bore through inlet passage 26' past the forward surface of the central spool on the distribution valve and throughpassage 30 and consequently the hammer piston is moved rearwardly. The exhaust now takes place through passage 29 past the forward surface of therear spool 24 and through the exhaust passage 27 to atmosphere. As soon as the hammer piston 3 has uncovered the throwing passage 31, the distribution valve 23 is again shifted to its forward position and this cycle continues throughout the normal operation ofthe drill. i

When it is desired to effect a hole clean ing operation, theoperator presses against the push button 53 and moves the f plunger valve 42 rearvardly from the position shown in Fig. 3 to theposition shown in Fig. 2." At this time the grooves 47 and 48 onthe plunger valve 42 and the passages 49 and '50 1 and radial ports 51 and 52 forma by-pass establishing communication. between. the op.- posite ends of the distribution valve 23, there by causing the opposing pressures at the ence of the distribution valve 'to be equalized. Upon further rearward movement of the plunger valve 42, the shoulder 46 thereon directly engages'theforward end surface of'the distribution valve 23, thereby permitting the latter to be manually shiftedwith faci ty tion shown in Fig. 1 against the relatively small opposing pressure acting on the central spool 25. lVlien the distribution valve 23 is Ill] held in its retracted position as shown in Fig.

1, pressure fluid flows from the inlet 26 past the drill steel 7 to the bottom of the hole;

[is soon as the manual pressure on the push button isrcleased, the valve 42 will autoinati cally return to its inoperative position and the val e 23 will then resume its normal op eration and the drill will again function in the normal manner. This and other uses and advantages of this, invention will be clearly apparent to those skilled in this art.

While I have in this application specifically described'one form which my invention may assume in practice, it will be understood that this torm of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is: g V 1, In a fluid actuated rock drill of the hammer type, the combination of a cylinder and a hammer piston reciprocable therein, a valve chest and'a fluid distributing valve therein controlling both the supply and exhaust of press re fluid for said cylinder, valve throwing passages between opposed spaces in thevalve chestand the cylinder bore for supplying pressure fluid for actuating said valve,

and manuallyoperable valve means to establish communication between the valve-chest spaces at the opposite ends of the valve for equalizing the pressures and means movable with said valve means to shift and hold the distributing va ve immovable;

2. In a fluid actuated rock drill of thehammer type, the combination of a cylinder and a hammer piston reciprocable therein, a valve chestand a fluid distributing valve therein controlling both the supply and exhaust of 3. y In a fluid actuated rock drill of the ham' -f mer type, the combination of a cylinder and a hammer piston reciprocable therein, a Valve chest and a fluid distributing valve therein'controlling both the supply and exhaust of pressure fluid for said cylinder, valve throwing passages between opposed spaces in the valve chest and the cylinder bore for supplying pressure fluid for actuating said valve, and manually operable means including an element arranged coaxially with said distribution valve and extending there through and havingvalve means for establishing communicationbetween the valve chest spaces at the opposite ends of the valve, said element also having means for directly engaging said valve to shift and hold the latter immovable.

4:. In a fluid actuated rock drill ofthe hammer type, the combination of a cylinder and a hammer piston reciprocable therein, a valve chest and a fluid distributing valve therein for controllin both the supply and exhaust of pressure fIuid for said cylinder, valve throwing passages between opposed spaces in the valve chest and the cylinder bore for supplying pressure fluid for actuating said valve, and a hole blowing device comprising a valve arranged coaxially with said distribution valve and having a bypass therein for directly connecting said opposed valve chest spaces to equalize the throwing pressures acting on the opposite ends of said distribution valve, and means for positively shifting and holding said distribution valve in one position. i V

5. In a fluid actuated rock drill of the ham,- mer type, the combination of a cylinder and a hammer piston reciprocable therein, a valve chest and a fluid distributing valve therein for controlling both the supply and exhaust of pressure fluid for said cylinder, valve throwing passages between opposed spaces in the valve chest and the cylinder bore for supplying pressure fluid foractuating said valve, and a hole blowing device comprising a valve arranged coaxially with said distribution valveand extending therethrough and having a bypass therein for directly connecting said opposed valve chest spaces to equal-- ize the throwing pressures acting on the op posite ends of said distribution valve, and means for positively shifting and holding said distribution valve in one position.

6. In a fluid actuated rock drill of the hammer type, the combination of acylinder and a hammer piston reciprocable therein, a valve chest and a fluid distributing valve therein controlling both the supply and exhaust of pressure fluid for said cylinder, valve throwing passages between opposed spaces in the valve chest and the cylinderbore for supplying pressure fluid for actuating said valve,a nd a hole blowing device comprising a manually operable valvemeans arranged coaxially with said distribution valve andextending therethrough for establishing communication belea tween said opposed valve chest spaces, and means for positively shifting and holding said distribution valve in one position.

7. In a fluid actuated rock drill of the hammer type, the combination of a cylinder and a hammer pistonreciprocable therein, a. valve chest and a fluid distribution valve therein controlling both the supply and exhaust of pressure fluid for said cylinder, valve-throwing passages between opposed spaces in the valve chestand the cylinder bore for supplying pressure fluid for actuating said valve, and a hole blowing device including a nianuallyoperable plunger valve arranged coaxially with said distribution valve and eX- tending therethrough and having a by-pass therein for directl connectin said iosed valve chest spaces for equalizing the pressures at the opposite ends ofvsaid valve, and

means for mechanically shifting and holding saidvalve in one position.

8. In a fluid actuated rock drill of the hammer type, the combination of a cylinder and a hammer piston reciprocable therein, a valve chest, a fluid distribution valve therein controlling; both the supply and exhaust of pres sure fluid for said cylinder, buii'er plugs for limiting movement or said valve in opposite directions, said plugs each having a central bore and ports connecting said bores with opposed-spaces in the valve chest at the opposite ends of the valve, valve throwing passages between said opposed spaces and the cylinder bore for supplying pressure fluid for actuating" said valve, and a hole blowing device including a manually operable plunger valve arranged coaitially with said distribution valve and sli'dably mounted in the bores in said butler-plugs, said plunger valve havinga by-passtherein for connectingthe ports in said butler plugs to equalize the pressures at the opposite ends of said distrib-u-tlion valve, and means for mechanically shifting and holding said valve in one position.

9. In a fluid actuated rock drill of the hammer type, the combination of a cylinder and a hammer piston'reciprocable therein, a valve chest and a fluid distributing valve therein controlling both the supply and exhaust of pressure fluid for said'cylinder, valve throwing passages between opposed spaces in the valve chest and the cylinder bore forsupplying pressure fluid for'actuating. said valve, and a hole blowing device including a manually operable plunger valve having means for establishing direct communication between said opposed pressure spaces for equalizing the pressures tending to throw said distribution valve, and means for mechanically shifting and holding said valve in one position.

10. In a fluid actuated rock drill of the hammer type, the combination of a cylinder and a hammer piston reciproeable therein, a- ,valve chest and a fluid distribution valve there-in controlling both the supply and eiihaust of pressure fluid for saidcylinder,

trib-ution valve, and means for mechanically shifting and holding said valve in one position. 7 1 c V 11-. In a fluid actuated rock drill of the hammer type, the combination of a cylinder and a hammer piston reciprocabletherein, a valve chest and a fluid distribut on valve therein controlling both the supply andexhaust of pressure fluid for said cylinder, valve throwing passages between opposed spaces in the valve chest andthe cylinder bore for supplying pressure fluid for ac tuating said valve, and a hole blowing de-' vice including atmanually operable plunger valvearranged coaxially with said'distribution valve and extending therethrougli for establishing comn'iunication between said op posed pressure spaces for equalizing the pressures tending to throw said distribution valve, and means for mechanically shifting;

and holding said valve in one'position.

12. In a fluid actuate drock drill of the I hammer type, the combination of a cylinder and a hammer pistoirreciproc'able therein, a

valve chest and a vfluid distribution valve therein controlling both the supply and eX-- haust of pressurefluid for said cylinder, valve throwing passages between opposed spaces in the valve'eliest and the cylinder bore for supplying pressure fluid for actuating said valve, anda hole. blowing device inv eluding a manually operable valve for establishing communication between said opposed valve chest spaces toequalize the pressures tending to throw said dist 'ibution valve, said valve being adapted to directly engage said distribution valve for shifting and liolding the latter immovable to effect a hole blowing operation. V

13. In a fluid :ctuated rock drill of the hammer type, the combination of a cylinder 7 and a hammer piston-'reciprocable thereinpa valve chest and a fluid distributing'valve therein controlling both the supply and ex haust of pressure fluid for said cylinder,

valve throwing passages between opposed spaces in the valve chest and the. cylinder bore for supplying pressure fluid for actuating said valve, and ahole blowing device.

including means for establishing communication between said opposed valve chest spaces to equalize the pressures tending to throw said valve and for'direct'ly engaging said distribution valve to shift and hold the latter immovable to effect a hole blowing operation 14. In a fluid actuated rock drill of the hammer type, the combination of a cylinder and a hammer piston reciprocable therein, a valve chest and a fluid distributing valve therein controlling both the supply and eX- haust of pressure fluid for said cylinder, valve throwing passages between opposed spaces in the valve chest and the cylinder bore for supplying pressure fluid for actuating said valve, and a hole blowing device including means arranged coaxially with said distribution valve for establishing direct communication between said opposed valve chest spaces for equalizing the pressures tending to throw said valve, and means for mechanically shifting and holding said valve inone position to effect a hole blowing operation.

In testimony whereof I afiix my signature.

CHARLES F. oseoon. 

